1. Field of the Invention
This invention relates to a bracket mounting arrangement for machine frames and, in particular, to a bracket mounting arrangement for interconnecting the horizontal and vertical frame members of core molding machine frames.
2. Description of the Related Art
Core molding machine frames typically include lower and upper horizontal support frame assemblies connected together by a plurality of vertical posts. Lower and upper platens are supported on the lower and upper support frames, respectively, and are adapted for vertical movement toward and away from each other through hydraulics or other conventional means. Lower and upper core molds are attached to the lower and upper platens, respectively, and are positioned on the platens so that the molds are in mutual alignment for a molding operation. The vertical posts are typically secured to the lower and upper frames through mounting bolts that are either parallel or perpendicular to the vertical posts. As the core molds are pressed toward each other and come into mutual contact during the molding process, opposing forces from the hydraulics put the core molds in compression. Equal but opposite tensile forces are transmitted to the vertical posts, and consequently, the mounting bolts are subjected to shear or tensile forces. The shear or tensile forces tend to deform the bolts along their longitudinal axis, and depending on the orientation at which the bolts are mounted, they can either bend or their threads can become worn or stripped. The bolts may also suffer from work hardening due to repeat cycling of the core molding operation. In any event, movement between the cross members and vertical posts eventually occurs and consequently affects the quality of the molded components. Eventual failure of the connection between the vertical posts and cross members can lead to disastrous results, high repair costs, and machine down time.